Wearable devices for delivering medicament to a patient are sometimes worn by the patient for a significant length of time in order to allow the medicament to be delivered at a desired rate or over a desired time period. An example of this type of wearable device is a bolus injector, which is typically worn like a patch against the skin. A bolus injector generally carries out automated subcutaneous delivery of relatively large volumes of liquid medicament to the patient, such as at least 1 ml. The delivery of the medicament can last for several minutes or hours. Such high capacity bolus injector devices can be called large volume devices (LVDs).
After the delivery of the medicament has been completed, the patient must remove the device from his or her body at some later time.